For many years dentistry has enhanced the quality of life of mankind by providing crowns for damaged, decayed or disfigured teeth. When a tooth is partially broken off, is disfigured caused by discoloration or has been damaged by decay, a modern dentist can restore the tooth both in function and appearance to a desired external shape by applying a crown. As commonly practiced today, a dentist first takes an impression employing a plastic material of the patient's teeth, typically an impression will include all of the patient's upper teeth or all of the patient's lower teeth. From such impression a mold is easily made by filling the impression with plaster that hardens and, after hardening, is easily removable from the soft plastic mold to faithfully replicate a patient's upper or lower teeth, including the adjacent gum areas. The dentist then prepares the damaged tooth to receive a crown by removing external portions, that is by grinding away external parts to reduce the total dimensional size of the tooth to be crowned so that all exterior portions thereof are confined within an area less than that of the desired crown. After the tooth has been prepared by removing exterior portions, a second impression is taken from which a second plaster mold is made.
These plaster molds are then sent off to a dental laboratory where a laboratory technician can manufacture a crown. After the crown is completed it is returned to the dentist who then cements it in place on the patient's prepared tooth.
This procedure works satisfactorily except that it takes several days up to several weeks from the time the dentist makes the impressions until the crown is returned to the dentist for installation in the patient's mouth. Typically when a tooth is prepared to receive a crown it is very visually distractive. To enable a patient to function both physically, that is to masticate food, and to function socially, that is to have a reasonable appearance, the typical procedure is that the dentist forms a temporary crown by molding temporary crown forming material on the prepared tooth and shaping it and hardening it in the patient's mouth so that hopefully the temporary crown will last until the crown to be formed in the dental laboratory is ready for installation.
Preparing a temporary crown has been a problem in the dental profession for many years since such temporary crowns frequently break or dislodge before the patient returns to the dental office to receive the permanent crown. Further and of even more significance is that the total procedure presently employed for crowning a tooth is time consuming on the part of the dentist and on the part of the patient since it requires the patient to make two separate visits to the dental office. The current procedure that requires a dentist to perform all of the dental work in his office whereas the crown itself is manufactured at a remote location not only creates inefficiency but adds to the expense. The primary problem, however, in today's dentistry with the crowning of a tooth is the inconvenience to the patient and the time constraints placed on the dentist. Further, problems with temporary crowns have always been a concern to dentists.
A method will be described herein in which a dentist can, with a single office visit by a patient, provide the patient a permanent crown. Stating it another way, a basic objective of the invention herein is a method of preparing a tooth and installing on the prepared tooth a permanent crown that can be done by a dentist entirely within his dental office.